A gas turbine includes a rotor that rotates around an axis and a casing that covers this rotor. The rotor has a rotor shaft and a plurality of rotor blades mounted on this rotor shaft. A plurality of stator blades are provided on the inner side of the casing.
The rotor blade has a blade body extending in the radial direction of the axis, a platform provided on the radially inner side of the blade body, and a blade root provided on the radially inner side of the platform. The blade body of the rotor blade is disposed in a combustion gas flow passage through which combustion gas passes. The platform defines the position of the combustion gas flow passage on the radially inner side. The blade root is fixed to the rotor shaft. The stator blade has a blade both extending in the radial direction of the axis, an inner shroud provided on the radially inner side of the blade body, and an outer shroud provided on the radially outer side of the blade both. The blade body of the stator blade is disposed in the combustion as flow passage through which the combustion gas passes. The inner shroud defines the position of the combustion gas flow passage on the radially inner side. The outer shroud defines the position of the combustion gas flow passage on the radially outer side.
Both the stator blades and the rotor blades of the gas turbine are exposed to high-temperature combustion gas. Therefore, these stator blades and rotor blades are commonly cooled with air etc.
For example, various cooling channels through which cooling air passes are formed in the stator blade described in Patent Literature 1. Specifically, a cavity which extends in the radial direction and into which cooling air flows is formed in the blade body of this stator blade. A plurality of discharge holes that communicate with the cavity of the blade body and extend in the direction of the chord of the blade body are formed in the inner shroud and the outer shroud. These discharge holes are open in a back end surface of the inner shroud and a back end surface of the outer shroud. The plurality of discharge holes are arrayed in the circumferential direction relative to the axis.